<!DOCTYPE html>
<html lang="en">
    <head>
        <meta charset="utf-8">
        <style type="text/css">
        		* {
        			padding: 0;
        			margin: 0;
        		}
			nav{
				width: 200px;
				height: 200px;
				background-color: skyblue;

			}
			p{
				height: 100px;
				/* width: 200px; */
				padding-top: 20px;
				background-color: red;
				padding-left: 20px;
				margin-top: 20px;

			}
			div {
				width: 300px;
				height: 200px;
				background-color: pink;
				padding-top: 10px;
				
			}
			div.dd {
				width: 200px;
				height: 100px;
				background-color: yellowgreen;

				
			}
			div.ddd{
				width: 100px;
				height: 100px;
				background-color: yellow;
				/* margin-top: 10px; */
			}
        </style>
    </head>
    <body>
    <nav>
    	<p>haha</p>
    </nav>
    <div>
    	<div class="dd">
    		<div class="ddd"></div>
    	</div>
    </div>
    </body>
</html>